default value

api/controllers/ApplicationController.php

@@ -25,7 +25,7 @@ class ApplicationController extends BaseController
     public function actionIndex()
     {
         $condition = [];
-        $platform_id = Yii::$app->request->post('platform_id');
+        $platform_id = Yii::$app->request->post('platform_id', 1);
         if(!empty($platform_id)){
             $condition = ['platform_id' => $platform_id];
         }